1. Field of the Invention
The present invention relates to a movable floor apparatus for a ship, and more particularly, to a floor apparatus for a ship, which is installed to be vertically movable with a vertical movement of a thruster canister within a vertical trunk of a hull.
2. Description of the Related Art
A ship is equipped with a thruster assembly for implementation of propulsion and position control. Such a thruster assembly is widely used in a ship which frequently moves its position, like a drill ship.
In particular, a drill ship is configured to have a self position control function of making the ship maintained stably at a predetermined drilling site on the sea, and to make a voyage with its own power. A thruster assembly, one of propulsion systems, is used as essential equipment for implementation of main propulsion and self position control. For example, three thruster assemblies are installed in a bow side of a drill ship, and three thruster assemblies are installed in a stern side thereof. The respective thruster assemblies are provided with 360-degree-rotatable propellers. Therefore, the thruster assembly can provide both the propulsion and the position control to cause the ship to be propelled, reversely propelled or rotated.
A thruster assembly may include an underwater unit with a propeller, and a thruster canister installed on the underwater unit. A driving motor for driving the propeller, a hydraulic system, a lubricating device, and so on, are installed in the thruster canister.
The thruster canister is installed to be vertically movable within a vertical trunk of a hull. When the thruster assembly is repaired or maintained or the ship passes through shallow water, such as a canal, the thruster canister is lifted up within the vertical trunk of the hull.
Meanwhile, an arctic drill ship used in arctic regions is configured such that various loading and unloading operations are carried out within the hull in order to avoid outworking under arctic environments. To this end, a landing floor on which side-dish containers or the like can be landed is required above the vertical trunk in which the thruster assembly is installed, that is, below a main deck of the hull. In particular, it is necessary to configure the landing floor which can avoid interference with a thruster canister which vertically moves within the vertical trunk and can facilitate the loading and unloading operations within the hull.